U.S. Pat. No. 4,899,523 issued February 1990 (Frumholtz) assigned to Kuhn discloses a mower including two groups of cutter disks, where the groups are separated at the center with each group including drive elements from each disk to the next. Drive is communicated to the two groups from an input drive shaft from the tractor to the center of the mower with a pair of outwardly extending drive shafts each extending to a vertical input shaft at the end cutter disk.
U.S. Pat. No. 4,253,294 (Zweegers) issued Mar. 3, 1981 discloses a mowing machine has a plurality of cutting disks rotatably supported on a cutter bar beneath the cutting disks. The cutting disks are driven by a horizontal drive shaft extending above the cutting disks coupled to a tractor power take-off shaft. The drive shaft is directly coupled through respective gear boxes with vertical shafts upon which are mounted the two outermost cutting disks. Drive between the disks is effected by a shaft extending along the cutter bar.
U.S. Pat. No. 4,848,069 (Ermacora) issued Jul. 18, 1989 and assigned to Kuhn discloses a mower which comprises two groups of cutting disks each mounted on a cutting bar where the cutting bars are connected to one another by a joint and are connected to the frame by a suspension.
U.S. Pat. No. 4,860,527 Maarten Koorn issued Aug. 29, 1989 and assigned to Van Der Lely discloses a mowing machine comprising at least three cutter disks on a supporting cutter bar. A rotating torsion shaft which is driven at both ends by drive shafts from a center power input is mounted in the cutter bar and carries gears for driving the disks.
U.S. Pat. No. 5,179,822 (McLean) issued Jan. 19, 1993 and assigned to Ford New Holland discloses a mower conditioner which includes a cutter bar defined by two sections separated at the center carried by a header that is suspended from a frame. The cutter bar has a plurality of individual cutting disks with two end cutting disks located adjacent opposed sides of the frame and intermediate cutting disks disposed between the end cutting disks. Input drive shafts deliver power from a power-take-off shaft on the tractor to a pair of generally vertical output drive shafts, via a bevel gearbox and a spur gearbox, connected to two of the intermediate cutting disks. The intermediate disks drive the remaining disks of that section by a shaft along the cutter bar.
U.S. Pat. No. 5,463,852 reissued as RE 40611 (O'Halloran) issued Nov. 7, 1995 to Hay and Forage (AGCO) discloses a harvester which has a series of rotary cutter disks on a cutter bar extending across the path of travel of the machine and rotatable about individual upright axes. The cutter bar is a flat gear case containing a train of intermeshed spur gears that serve to distribute power between the disks. Each end of the cutter bar has a hollow, gearless extension welded thereto which supports at least one additional outboard cutter disk that receives its driving power exteriorly of the cutter bar. One embodiment uses a mechanical drive to bring power to the upright shaft of the cutter disk having the first spur gear so that the cutter disks with gears receive all their power from the driven cutter. The outboard cutters not having gears are driven by an exterior, over-the-top drive mechanism. As an alternative to a mechanical drive, the cutter bar may utilize a pair of hydraulic motors coupled with the shafts of the first and last disks. All of the gears in the gear case remain positively enmeshed with one another in the gear train, so that the two hydraulic motors share the total load of driving the cutter bed.